Display device and method of manufacturing the same

ABSTRACT

A display device and a method of manufacturing a display device are provided. A manufacturing method of a display apparatus includes forming a display module including a first area and including a display panel including lower and upper surfaces opposite each other, a first film under the lower surface of the display panel, a second film on the upper surface of the display panel, and an adhesive layer between the lower surface of the display panel and the first film; weakening an adhesive force of a first adhesive portion of the adhesive layer in the first area to be weaker than an adhesive force of a second adhesive portion of the adhesive layer outside the first area; cutting the first film and the adhesive layer; and removing a portion of the first film and the first adhesive portion from the first area.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.16/532,952, filed Aug. 6, 2019, which is a divisional of U.S. patentapplication Ser. No. 16/160,803, filed Oct. 15, 2018, now U.S. Pat. No.10,411,219, issued Sep. 10, 2019, which is a divisional of U.S. atentapplication Ser. No. 15/409,491, filed Jan. 18, 2017, now U.S. Pat. No.10,141,540, issued Nov. 27, 2018, which claims priority to and thebenefit of Korean Patent Application No. 10-2016-0072735, filed on Jun.10, 2016 in the Korean Intellectual Property Office, the entire contentof each of which is incorporated herein by reference.

BACKGROUND 1. Field

The present disclosure relates to a display device and a method ofmanufacturing the same. More particularly, the present disclosurerelates to an organic light emitting display device and a method ofmanufacturing the organic light emitting display device.

2. Description of the Related Art

An organic light emitting display device includes a plurality of pixels.Each pixel includes an organic light emitting diode and a circuit partcontrolling the organic light emitting diode. The circuit part includesat least a control transistor, a driving transistor, and a storagecapacitor.

The organic light emitting diode includes an anode, a cathode, and anorganic light emitting layer disposed between the anode and the cathode.The organic light emitting diode emits a light when a voltage greaterthan a threshold voltage of the organic light emitting layer is appliedbetween the anode and the cathode.

SUMMARY

According to an aspect, the present disclosure provides a display deviceincluding a display module easily bent in a bending area and having asmall radius of curvature by providing a groove overlapped with thebending area in a first film and an adhesive layer.

According to another aspect, the present disclosure provides a method ofmanufacturing a display device capable of easily removing a portion ofthe adhesive layer and a portion of the first film in a target areaafter forming the adhesive layer and the first film on a display panel.

According to one or more embodiments of the inventive concept, a methodof manufacturing a display device includes: forming a display moduleincluding a first area defined therein, the display module including adisplay panel including a lower surface and an upper surface oppositethe lower surface, a first film under the lower surface of the displaypanel, a second film on the upper surface of the display panel, and anadhesive layer between the lower surface of the display panel and thefirst film; weakening an adhesive force of a first adhesive portion ofthe adhesive layer in the first area to be weaker than an adhesive forceof a second adhesive portion of the adhesive layer outside the firstarea; cutting the first film and the adhesive layer along an edge of thefirst area; and removing a portion of the first film and the firstadhesive portion from the first area.

According to an embodiment, the cutting the first film and the adhesivelayer is performed after the weakening the adhesive force.

According to an embodiment, the display module includes a display areato display an image and a non-display area adjacent to the display area,and the first area is defined in the non-display area.

According to an embodiment, the weakening the adhesive force includesirradiating an ultraviolet ray to the first area along an upperdirection extending from the lower surface of the display panel to theupper surface of the display panel.

According to an embodiment, the cutting the first film and the adhesivelayer is performed by irradiating a laser beam along the upperdirection.

According to an embodiment, the laser beam is a CO2 laser beam or an UVlaser beam.

According to an embodiment, the first area crosses the display module ina first direction when viewed in a plan view, and the cutting the firstfilm and the adhesive layer includes irradiating the laser beam to afirst edge of the first area extending in the first direction andirradiating the laser beam to a second edge of the first area extendingin the first direction and spaced apart from the first edge of the firstarea.

According to an embodiment, the method further includes bending thedisplay module with respect to a reference axis defined in the firstarea and extending in the first direction.

According to an embodiment, the removing the portion of the first filmand the first adhesive portion is performed within one hour after thecutting the first film and the adhesive layer is performed.

According to one or more embodiments of the inventive concept, a displaydevice includes a display panel, a first film, a second film, and anadhesive layer. The display panel includes a first area defined thereinand includes a lower surface and an upper surface opposite the lowersurface. The first film is under the lower surface of the display paneland includes a film groove defined therein to overlap with the firstarea. The second film is on the upper surface of the display panel. Theadhesive layer is between the lower surface of the display panel and thefirst film and includes an adhesive groove defined therein to overlapwith the first area.

According to an embodiment, a surface roughness of a first portion ofthe lower surface of the display panel in the first area is differentfrom a surface roughness of a second portion of the lower surface of thedisplay panel outside the first area.

According to an embodiment, the surface roughness of the first portionof the lower surface of the display panel is greater than the surfaceroughness of the second portion of the lower surface of the displaypanel.

According to an embodiment, the first portion of the lower surface ofthe display panel is exposed by the film groove and the adhesive groove.

According to an embodiment, an angle between the second portion of thelower surface of the display panel and each of an inner surface of thefirst film defining the film groove and an inner surface of the adhesivelayer defining the adhesive groove is an acute angle.

According to an embodiment, the display panel includes a base substrate,a driving layer, an organic light emitting diode, and a sealing layer.The base substrate defines the lower surface and includes polyimide. Thedriving layer is on the base substrate. The organic light emitting diodeis on the driving layer. The sealing layer covers the organic lightemitting diode.

According to an embodiment, a first base substrate portion of the basesubstrate in the first area has a first thickness, and a second basesubstrate portion of the base substrate outside the first area has asecond thickness greater than the first thickness.

According to an embodiment, the adhesive layer covers the first portionof the lower surface of the display panel, a first adhesive layerportion of the adhesive layer in the first area has a third thickness,and a second adhesive layer portion of the adhesive layer outside thefirst area has a fourth thickness greater than the third thickness.

According to an embodiment, the display device further includes carbidescontacting the first portion of the lower surface of the display panel.

According to an embodiment, the display device further includes a burron a lower surface of the first film adjacent to the film groove.

According to an embodiment, the display panel includes a display area todisplay an image and a non-display area adjacent to the display area,and the first area is defined in the non-display area.

According to an embodiment, the display panel includes a display area todisplay an image and a non-display area adjacent to the display area,and the first area is defined to cross the display area.

According to an embodiment, the first area crosses the display panel ina first direction when viewed in a plan view and is bent with respect toa reference axis defined in the first area and extending in the firstdirection.

According to an embodiment, the first film includes polyethyleneterephthalate.

According to an embodiment, the second film includes a polarizing plate.

According to one or more embodiments of the inventive concept, a displaydevice includes a display panel, a first film, a second film, and anadhesive layer. The display panel includes a first area defined thereinand includes a lower surface and an upper surface opposite the lowersurface. The first film is under the lower surface of the display paneland includes a film groove defined therein to overlap with the firstarea. The second film is on the upper surface of the display panel. Theadhesive layer is between the lower surface of the display panel and thefirst film and includes an adhesive groove defined therein to overlapwith the first area. The display panel includes a base substratedefining the lower surface of the display panel, a first portion of thebase substrate in the first area having a first thickness, and a secondportion of the base substrate outside the first area having a secondthickness greater than the first thickness.

According to an embodiment, the base substrate includes polyimide.

According to an embodiment, a surface roughness of the first portion ofthe base substrate is greater than a surface roughness of the secondportion of the base substrate.

According to an embodiment, the first area crosses the display panel ina first direction when viewed in a plan view and is bent with respect toa reference axis defined in the first area and extending in the firstdirection.

According to an embodiment, the display panel includes a display area todisplay an image and a non-display area adjacent to the display area,and the first area is defined in the non-display area.

According to an embodiment, the display device further includes aprinted circuit board connected to the non-display area of the displaypanel, and the first area is bent with respect to the reference axisbetween the display area and the printed circuit board.

According to aspects of the display device, the groove is provided tothe first film and the adhesive layer to overlap with the bending area,and thus the display module may be easily bent in the bending area, andthe radius of curvature of the display module may become small.

According to aspects of the manufacturing method of the display device,after the adhesive layer and the first film are formed on the entiresurface of the display panel, the portion of the adhesive layer and theportion of the first film, which are disposed in the target area, may beeasily removed.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects and advantages of the present disclosurewill become readily apparent by reference to the following detaileddescription when considered in conjunction with the accompanyingdrawings wherein:

FIG. 1 is a flowchart showing a method of manufacturing a display deviceaccording to an exemplary embodiment of the present disclosure;

FIG. 2 is a plan view showing a mother substrate according to anexemplary embodiment of the present disclosure;

FIG. 3 is a plan view showing a display module of FIG. 2;

FIG. 4 is a cross-sectional view taken along a line I-I′ of FIG. 3;

FIG. 5 is a cross-sectional view showing a stacking structure of adisplay panel of FIG. 4;

FIG. 6 is a cross-sectional view showing a portion of a display panelcorresponding to one pixel area;

FIGS. 7 to 9 are cross-sectional views taken along the line I-I′ of FIG.3;

FIG. 10A is a photograph showing a lower surface of a base substratewhen a removing operation is performed within one hour after a cuttingoperation is performed;

FIG. 10B is a photograph showing a portion of a first film removed in aremoving operation when the removing operation is performed within onehour after a cutting operation is performed;

FIG. 11A is a photograph showing a lower surface of a base substratewhen a removing operation is performed after one hour elapses from atime point at which a cutting operation is performed;

FIG. 11B is a photograph showing a portion of a first film removed in aremoving operation when the removing operation is performed after onehour elapses from a time point at which a cutting operation isperformed;

FIG. 12 is a perspective view showing an organic light emitting displaydevice according to an exemplary embodiment of the present disclosure;

FIG. 13 is a plan view showing the organic light emitting display deviceof FIG. 12;

FIG. 14 is a cross-sectional view taken along a line II-II′ of FIG. 13;

FIG. 15 is a cross-sectional view taken along the line II-II′ of FIG. 13when the organic light emitting display device is bent;

FIGS. 16 to 19 are cross-sectional views showing display modulesaccording to exemplary embodiments of the present disclosure;

FIG. 20 is a plan view showing a display module according to anotherexemplary embodiment of the present disclosure;

FIG. 21 is a plan view showing the display module of FIG. 20 in a bentstate;

FIG. 22 is a perspective view showing an organic light emitting displaydevice according to another exemplary embodiment of the presentdisclosure;

FIG. 23 is a plan view showing the organic light emitting display deviceof FIG. 22;

FIG. 24 is a cross-sectional view taken along a line III-III′ of FIG.23; and

FIG. 25 is a cross-sectional view taken along the line III-III′ of FIG.23 when the organic light emitting display device is bent.

DETAILED DESCRIPTION

The following description with reference to the accompanying drawings isprovided to assist in a comprehensive understanding of variousembodiments of the present disclosure as defined by the claims and theirequivalents. It includes various specific details to assist in thatunderstanding but these are to be regarded as merely exemplary.Accordingly, those of ordinary skill in the art will recognize thatvarious changes and modifications of the various embodiments describedherein can be made without departing from the scope and spirit of thepresent disclosure.

It will be understood that when an element or layer is referred to asbeing “on,” “connected to,” or “coupled to” another element or layer, itcan be directly on, connected, or coupled to the other element or layer,or intervening elements or layers may be present. In contrast, when anelement is referred to as being “directly on,” “directly connected to,”or “directly coupled to” another element or layer, there are nointervening elements or layers present.

Hereinafter, some exemplary embodiments of the present invention will beexplained in further detail with reference to the accompanying drawings.

FIG. 1 is a flowchart showing a method of manufacturing a display deviceaccording to an exemplary embodiment of the present disclosure; FIG. 2is a plan view showing a mother substrate according to an exemplaryembodiment of the present disclosure; FIG. 3 is a plan view showing adisplay module of FIG. 2; and FIGS. 4 and 6 to 9 are cross-sectionalviews taken along a line I-I′ of FIG. 3.

Referring to FIGS. 1 and 2, a mother substrate 2000 including a displaymodule 1000 is formed (S10).

The mother substrate 2000 includes a plurality of display modules 1000and a dummy part DM. The display modules 1000 are formed using onesubstrate.

In FIG. 2, the mother substrate 2000 including six display modules 1000is shown, but the number of the display modules 1000 is not limited tosix. That is, the number of the display modules 1000 included in onemother substrate 2000 may be greater than or less than six.

The display modules 1000 and the dummy part DM may be flexible.Accordingly the mother substrate 2000 may be flexible.

Each of the display modules 1000 displays an image in response to asignal applied thereto. Each of the display modules 1000 may include anyof various types of display panels, but, hereinafter, the displaymodules 1000 including an organic light emitting display panel will bedescribed.

The dummy part DM is disposed between the display modules 1000. Thedummy part DM is disposed adjacent to an edge of each of the displaymodules 1000 to surround the display modules 1000. The dummy part DM maybe finally removed in the manufacturing process of the display device.

Hereinafter, directions in which two adjacent sides of the displaymodule 1000 extend are respectively referred to as a first direction DR1and a second direction DR2. In FIG. 2, the first direction DR1corresponds to a direction in which short sides of the display module1000 extend, and the second direction DR2 corresponds to a direction inwhich long sides of the display module 1000 extend. However, the firstdirection DR1 and the second direction DR2 may be changed with respectto each other according to embodiments.

When viewed in a plan view, the display module 1000 includes a displayarea DA and a non-display area NA defined therein. The image isdisplayed through the display area DA and not displayed through thenon-display area NA. The non-display area NA is disposed adjacent to thedisplay area DA.

In FIG. 3, the non-display area NA is disposed adjacent to one side ofthe display area DA. In an embodiment, the display area DA and thenon-display area NA are disposed adjacent to each other in the seconddirection DR2, but are not limited thereto or thereby. That is, thenon-display area may be further defined adjacent to one or more of theother three sides of the display area DA.

A pad area PDA is defined in the non-display area NA. The pad area PDAis connected to a flexible printed circuit board (not shown), and thedisplay module 1000 receives signals required to drive itself throughthe pad area PDA.

A first area GRA may be further defined in the non-display area NA. Thefirst area GRA is defined between the pad area PDA and the display areaDA and spaced apart from the pad area PDA and the display area DA. Thefirst area GRA may correspond to an area in which a groove is definedwhen the organic light emitting display device according to the presentdisclosure is completely manufactured.

The first area GRA crosses the display module 1000 in the firstdirection DR1 when viewed in a plan view. A first edge EG1 and a secondedge EG2 of the first area GRA extend in the first direction DR1 and arespaced apart from each other.

As shown in FIG. 4, the display module 1000 includes a display panel100, a first film 200, a second film 300, and an adhesive layer 400.

The display panel 100 includes a lower surface 101 and an upper surface102. Hereinafter, a direction substantially vertical to the lowersurface 101 or the upper surface 102 of the display panel 100 and towardthe upper surface 102 from the lower surface 101 of the display panel100 is referred to as an upper direction DR3.

The first film 200 is disposed under the lower surface 101 of thedisplay panel 100. The second film 300 is disposed above the uppersurface 102 of the display panel 100. The adhesive layer 400 is disposedbetween the lower surface 101 of the display panel 100 and the firstfilm 200.

The first film 200 protects the display panel 100. The first film 200may include polyethylene terephthalate (PET), polyethylene naphthalate(PEN), polypropylene (PP), polycarbonate (PC), polystyrene (PS),polysulfone (PSul), polyethylene (PE), polyphthalamide (PPA),polyethersulfone (PES), polyarylate (PAR), polycarbonate oxide (PCO), ormodified polythenylene oxide (MPPO). In the present exemplaryembodiment, the first film 200 may include polyethylene terephthalate(PET) as a representative example.

The second film 300 includes a polarizing plate. The polarizing plateblocks an external light incident thereto. The polarizing plate includesa linear polarizing layer and a λ/4 retardation layer. The linearpolarizing layer is disposed on the λ/4 retardation layer. The externallight sequentially passing through the linear polarizing layer and theλ/4 retardation layer is reflected by a lower portion of the polarizingplate, e.g., a cathode of the display panel 100, and the reflectedexternal light becomes extinct since the reflected external light doesnot pass through the linear polarizing layer after passing through theλ/4 retardation layer.

The adhesive layer 400 adheres the display panel 100 to the first film200. The adhesive layer 400 may include a urethane-based material, anacrylic-based material, or a silicon-based material. The adhesive layer400 may be a pressure-sensitive adhesive layer.

FIG. 5 is a cross-sectional view showing a stacking structure of thedisplay panel 100; and FIG. 6 is a cross-sectional view showing aportion of the display panel 100 corresponding to one pixel area. Asshown in FIG. 6, one pixel is disposed in one pixel area PA.

The display panel 100 includes a base substrate 110, a driving layer120, an organic light emitting element layer 130, and a sealing layer140.

The base substrate 110 provides the lower surface 101 of the displaypanel 100. The base substrate 110 may be, but is not limited to, aflexible substrate and may include a plastic material having superiorthermal resistance and durability, e.g., polyethylene terephthalate(PET), polyethylene naphthalate (PEN), polycarbonate (PC), polyarylate(PAR), polyetherimide (PEI), polyethersulfone (PES), polyimide (PI),etc. The base substrate 110 may include polyimide as a representativeexample.

The driving layer 120 includes devices to apply signals to the organiclight emitting element layer 130. The driving layer 120 includes varioussignal lines, such as a scan line (not shown), a data line (not shown),a power source line (not shown), a light emitting line (not shown), etc.The driving layer 120 includes a plurality of transistors andcapacitors. The transistors include a switching transistor (not shown)and a driving transistor Qd, which are arranged in every one pixel (notshown).

FIG. 6 shows the driving transistor Qd of the driving layer 120 as arepresentative example. The driving transistor Qd includes an activelayer 211, a gate electrode 213, a source electrode 215, and a drainelectrode 217.

The active layer 211 is disposed on the base substrate 110. The drivinglayer 120 further includes a first insulating layer 221 disposed betweenthe active layer 211 and the gate electrode 213. The first insulatinglayer 221 insulates the active layer 211 from the gate electrode 213.The source electrode 215 and the drain electrode 217 are disposed on thegate electrode 213. The driving layer 120 further includes a secondinsulating layer 223 disposed between the gate electrode 213 and thesource electrode 215 and between the gate electrode 213 and the drainelectrode 217. The source electrode 215 and the drain electrode 217 areconnected to the active layer 211 respectively through contact holes CH1and CH2 formed through the first insulating layer 221 and the secondinsulating layer 223.

The driving layer 120 further includes a protective layer 230 disposedon the source electrode 215 and the drain electrode 217.

The present disclosure is not limited to the structure of the drivingtransistor Qd shown in FIG. 6, and positions of the active layer 211,the gate electrode 213, the source electrode 215, and the drainelectrode 217 may be changed in various ways. For instance, the gateelectrode 213 is disposed on the active layer in FIG. 6, but the gateelectrode 213 may be disposed under the active layer 211 according toembodiments.

Although a structure of the switching transistor is not shown in FIG. 6,the switching transistor (not shown) may have substantially the samestructure as that of the driving transistor Qd. However, the switchingtransistor may have a structure different from that of the drivingtransistor Qd according to embodiments. For instance, an active layer(not shown) of the switching transistor (not shown) may be disposed on alayer different from a layer on which the active layer 211 of thedriving transistor Qd is disposed.

The organic light emitting element layer 130 includes an organic lightemitting diode LD. In the present exemplary embodiment, the organiclight emitting diode LD is a front surface light emitting type organiclight emitting diode LD, and thus the organic light emitting diode LDemits a light to the upper direction DR3.

The organic light emitting diode LD includes a first electrode AE, anorganic layer OL, and a second electrode CE.

The first electrode AE is disposed on the protective layer 230. Thefirst electrode AE is connected to the drain electrode 217 through acontact hole CH3 formed through the protective layer 230.

The first electrode AE may be a pixel electrode or a positive electrode.The first electrode AE may be a transflective electrode or a reflectiveelectrode. In the case where the first electrode AE is the transflectiveelectrode or the reflective electrode, the first electrode AE mayinclude Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, or a mixture thereof.

The first electrode AE has a single-layer structure of a metal oxide ora metal or has a multi-layer structure of layers. For instance, thefirst electrode AE may have a single-layer structure of ITO, Ag, or amixture of metal, e.g., a mixture of Ag and Mg, a double-layer structureof ITO/Mg or ITO/MgF, or a triple-layer structure of ITO/Ag/ITO, but isnot limited thereto or thereby.

The organic layer OL includes an organic light emitting layer containinga low molecular weight or high molecular weight organic material. Theorganic light emitting layer emits the light. The organic layer OLselectively includes a hole transport layer, a hole injection layer, anelectron transport layer, and an electron injection layer in addition tothe organic light emitting layer.

Holes and electrons are injected into the organic light emitting layerof the organic layer OL from the first electrode AE and the secondelectrode CE, and the holes are recombined with the electrons in theorganic light emitting layer to generate excitons. The excitons emitenergy discharged when an excited state returns to a ground state aslight.

The second electrode CE is disposed on the organic layer OL. The secondelectrode CE may be a common electrode or a negative electrode. Thesecond electrode CE may be a transmissive electrode or a transflectiveelectrode. In the case where the second electrode CE is the transmissiveelectrode or the transflective electrode, the second electrode CE mayinclude Li, Ca, LiF/Ca, LiF/AI, Al, Mg, BaF, Ba, Ag, a compound thereof,or a mixture thereof, e.g., a mixture of Ag and Mg.

The second electrode CE includes an auxiliary electrode. The auxiliaryelectrode includes a layer formed by depositing the above-mentionedmaterials towards the organic light emitting layer and a transparentconductive oxide formed on the layer, such as indium tin oxide, indiumzinc oxide, zinc oxide, indium tin zinc oxide, Mo, Ti, Ag, etc.

The organic light emitting element layer 130 further includes a pixeldefinition layer PDL disposed on the protective layer 230. The pixeldefinition layer PDL is disposed to overlap with a boundary of the pixelarea PA when viewed in a plan view.

The sealing layer 140 is disposed above the organic light emittingelement layer 130. The sealing layer 140 provides the upper surface 102of the display panel 100. The sealing layer 140 blocks the organic lightemitting element layer 130 from external moisture and oxygen. Thesealing layer 140 includes a sealing substrate 141 and a sealing member(not shown). The sealing member (not shown) is disposed along an edge ofthe sealing substrate 141 and seals the organic light emitting diode LDtogether with the sealing substrate 141. An inner space 143 defined bythe sealing substrate 141 and the sealing member (not shown) ismaintained in a vacuum state. However, the inner space 143 may be filledwith nitrogen (N2) or with a filling member of an insulating material.

Different from the display panel 100, the sealing layer 140 may have astructure in which an organic layer and an inorganic layer are stackedmultiple times.

Referring to FIG. 7, the adhesive layer 400 includes a first adhesiveportion 410 defined in the first area GRA and a second adhesive portion420 defined outside the first area GRA.

Referring to FIGS. 1 and 7, an adhesive force of the first adhesiveportion 410 becomes weaker than an adhesive force of the second adhesiveportion 420 (S20).

In an embodiment, in the weakening of the adhesive force (S20), anultraviolet ray LZ1 is irradiated in the upper direction DR3 from alower side of the display module 1000 in the first area GRA. Theultraviolet ray LZ1 is irradiated by using a UV laser source.

When the ultraviolet ray LZ1 is irradiated, the adhesive force betweenthe first adhesive portion 410 and the base substrate 110 becomes weak.The adhesive force between the first adhesive portion 410 and the basesubstrate 110 becomes weak since carbides are generated on the lowersurface 101 of the base substrate 110 due to the ultraviolet ray LZ1 ora surface roughness of the lower surface 101 of the base substrate 110is changed due to the ultraviolet ray LZ1.

When the adhesive force of the first adhesive portion 410 is notweakened, it is difficult to remove a portion of the first film 200 andthe first adhesive portion 410, which are disposed in the first areaGRA, or the base substrate 110 may be damaged during the removal of theportion of the first film 200 and the first portion 410. Due tooperation S20, the portion of the first film 200 and the first portion410 may be stably removed in the following process.

Referring to FIGS. 1, 3, and 8, the first film 200 and the adhesivelayer 400 are cut along an edge of the first area GRA (S30).

In the cutting of the first film 200 and the adhesive layer 400 (S30), alaser beam is irradiated in the upper direction DR3 from the lower sideof the display module 1000 to cut the first film 200 and the adhesivelayer 400.

The laser beam may be irradiated using a CO₂ laser source having a highenergy efficiency or the UV laser source.

The cutting of the first film 200 and the adhesive layer 400 (S30)includes irradiating a laser beam LZ2 along the first edge EG1 of thefirst area GRA and irradiating a laser beam LZ3 along the second edgeEG2 of the first area GRA.

After the cutting of the first film 200 and the adhesive layer 400(S30), a first groove G1 is formed in the first film 200 and theadhesive layer 400 to overlap with the first edge EG1 of the first areaGRA, and a second groove G2 is formed in the first film 200 and theadhesive layer 400 to overlap with the second edge EG2 of the first areaGRA.

Each of the first groove G1 and the second groove G2 has a shape havinga width which gradually decreases upward along the upper direction DR3.An inner surface GS1 of the first groove G1 and an inner surface GS2 ofthe second groove G2 are inclined.

Since the laser beams LZ2 and LZ3 are irradiated in the cutting of thefirst film 200 and the adhesive layer 400 (S30), a burr BR is formed onthe lower surface of the first film 200 to be adjacent to the first andsecond grooves G1 and G2. The burr BR may be formed by a portion of thefilm 200, which is melted by heat energy of the laser beams LZ2 and LZ3.

If the cutting of the first film 200 and the adhesive layer 400 (S30) isperformed prior to the weakening of the adhesive force of the firstadhesive portion 410 (S20), the ultraviolet ray LZ1 irradiated in theupper direction DR3 is refracted by the inner surface GS1 of the firstgroove G1 and the inner surface GS2 of the second groove G2 andirradiated to an area smaller than the first area GRA, and the adhesiveforce of the adhesive layer disposed at the edge of the first area GRAmay not be weakened. However, the present exemplary embodiment does notexclude that the cutting of the first film 200 and the adhesive layer400 (S30) may be performed prior to the weakening of the adhesive forceof the first adhesive portion 410 (S20).

In the present exemplary embodiment, the cutting of the first film 200and the adhesive layer 400 (S30) may be performed after the weakening ofthe adhesive force of the first adhesive portion 410 (S20). Thus, thefirst film 200 and the adhesive layer 400 may be cut after theultraviolet ray LZ1 is uniformly irradiated to the first area GRAincluding the edge of the first area GRA in the weakening of theadhesive force of the first adhesive portion 410 (S20).

Referring to FIGS. 1 and 9, the portion of the first film 200 and theportion of the adhesive layer 400, which are disposed in the first areaGRA, are removed (S40).

Due to the removal of the portion of the first film 200 and the firstadhesive portion 410 of the adhesive layer 400 (S40), a groove GR isformed.

According to the manufacturing method of the display device of thepresent exemplary embodiment, the adhesive layer 400 and the first film200 are formed on the entire surface of the display panel 100, and thenthe portion of the adhesive layer 400 and the portion of the first film200, which are disposed in a target area, may be easily removed.According to the manufacturing method of the display device of thepresent exemplary embodiment, a manufacturing process may be simplifiedand a manufacturing cost may be reduced when compared with those ofprocesses of attaching a first film, from which a portion thereofcorresponding to a target area is removed, to the display panel 100.

FIG. 10A is a photograph showing a lower surface of a base substratewhen the removing operation S40 is performed within one hour after thecutting operation S30 is performed; and FIG. 10B is a photograph showinga portion of a first film removed in the removing operation S40 when theremoving operation S40 is performed within one hour after the cuttingoperation S30 is performed.

FIG. 11A is a photograph showing a lower surface of a base substratewhen the removing operation S40 is performed after one hour elapses froma time point at which the cutting operation S30 is performed; and FIG.11B is a photograph showing a portion of a first film removed in theremoving operation S40 when the removing operation S40 is performedafter one hour elapses from a time point at which the cutting operationS30 is performed.

Referring to FIGS. 10A and 10B, when the removing of the portion of thefirst film 200 and the portion of the adhesive layer 400 (S40) isperformed within one hour after performing the cutting of the first film200 and the adhesive layer 400 (S30), a portion ADH of the adhesivelayer 400 is removed with the portion of the first film 200.

An adhesive force between the lower surface 101 of the base substrate110 is smaller than that between the first film 200 and the adhesivelayer 400 during the one hour after performing the cutting of the firstfilm 200 and the adhesive layer 400 (S30).

Referring to FIGS. 11A and 11B, when the removing of the portion of thefirst film 200 and the portion of the adhesive layer 400 (S40) isperformed after one hour from a time point at which the cutting of thefirst film 200 and the adhesive layer 400 (S30) is performed, theportion ADH of the adhesive layer 400 remains on the lower surface 101of the base substrate 110, and only the portion of the first film 200 isremoved.

Referring to FIGS. 1 and 9 again, in the present exemplary embodiment,the removing of the portion of the first film 200 and the portion of theadhesive layer 400 (S40) may be performed within one hour afterperforming the cutting of the first film 200 and the adhesive layer 400(S30). Accordingly, after the removing of the portion of the first film200 and the portion of the adhesive layer 400 (S40) is performed, theportion ADH of the adhesive layer 400 is removed, and the lower surface101 of the base substrate 110 is exposed.

Then, the display modules 1000 may be separated from the mothersubstrate 2000 by removing the dummy part DM of the mother substrate2000. However, the process of separating the display modules 1000 fromthe mother substrate 2000 may be performed prior to the weakeningprocess (S20), the cutting process (S30), and the removing process(S40).

The display module 1000 is bent with respect to a reference axis definedin the first area GRA and extending in the first direction DR1. In thiscase, the display module 1000 may be bent such that two parts of thefirst film 200, which are separated by the groove GR, are closer to eachother.

FIG. 12 is a perspective view showing an organic light emitting displaydevice according to an exemplary embodiment of the present disclosure;FIG. 13 is a plan view showing the organic light emitting display deviceof FIG. 12; FIG. 14 is a cross-sectional view taken along a line II-II′of FIG. 13; and FIG. 15 is a cross-sectional view taken along the lineII-II′ of FIG. 13 when the organic light emitting display device isbent.

Referring to FIGS. 12 to 15, an organic light emitting display device DPincludes the display module 1000, a flexible printed circuit board FPC,and a printed circuit board PCB.

The flexible printed circuit board FPC includes a flexible wiring board122 and a driving circuit chip 125. The driving circuit chip 125 iselectrically connected to wirings of the flexible wiring board 122.

In the case where the flexible printed circuit board FPC includes thedriving circuit chip 125, data pads electrically connected to data linesand control signal pads electrically connected to control signal linesare arranged in a pad area (not shown) of the display panel 100. Thedata lines are connected to transistors arranged in the pixel, and thecontrol signal lines are connected to a scan driving circuit. In thepresent exemplary embodiment, the flexible printed circuit board FPC isprovided in a chip-on-film package, but is not limited thereto orthereby. According to another embodiment, the driving circuit chip 125may be mounted on the non-display area NA of the display panel 100, andthe flexible printed circuit board FPC may be a flexible wiring board.

The printed circuit board PCB is electrically connected to the displaypanel 100 through the flexible wiring board 122 to transmit and receivesignals to and from the driving circuit chip 125. The printed circuitboard PCB provides at least one of image data, a control signal, and apower source voltage to the display panel 100 or the flexible printedcircuit board FPC. The printed circuit board PCB may include activeelements and passive elements. The printed circuit board PCB may includea pad part (not shown) connected to the flexible printed circuit boardFPC.

The display module 1000 has a structure formed by the manufacturingmethod of the organic light emitting display device described withreference to FIGS. 1 to 9. The display module 1000 will be described infurther detail, and the same descriptions as those of FIGS. 1 to 9 willnot be reiterated.

The display module 1000 displays the image to the upper direction DR3.

The display module 1000 may be bent with respect to a reference axis AXextending in the first direction DR1. The reference axis AX may bedefined under the display module 1000. The display module 1000 may bebent such that two parts of the first film 200, which are divided by thegroove GR, are closer to each other.

The display module 1000 may be bent in the first area GRA. A bendingarea BA may be defined in the display module 1000. The display module1000 may be flat in an area other than the bending area BA. The bendingarea BA may have a width smaller than that of the first area GRA.

Since the adhesive layer 400 and the first film 200 have resilience whenthe adhesive layer 400 and the first film 200 are bent and the displaymodule 1000 requires more force to maintain the bent state as athickness of the display module 1000 increases, removing the adhesivelayer 400 and the first film 200 in the bending area BA facilitatesbending the display module 1000. According to the display device of thepresent exemplary embodiment, the groove GR is provided to the firstfilm 200 and the adhesive layer 400 to overlap with the bending area BA,and thus a radius of curvature of the display module 1000 becomes smallin the bending area BA.

FIGS. 16 to 19 are cross-sectional views showing display modulesaccording to exemplary embodiments of the present disclosure.

Display modules 1001 to 1004 will be described in further detail withreference to FIGS. 16 to 19.

Each of the display modules 1001 to 1004 may include the display panel100, the first film 200, the second film 300, and the adhesive layer400. A film groove GR1 may be defined in the first film 200 to overlapwith the first area GRA. A groove

GR2 may be defined in the adhesive layer 400 to overlap with the firstarea GRA.

In the display module 1001 shown in FIG. 16, the base substrate 110includes a first base substrate portion 111 disposed in the first areaGRA and a second base substrate portion 112 disposed outside the firstarea GRA. A first part of a lower surface of the display module 1001corresponds to a lower surface 11 of the first base substrate portion111, and a second part of the lower surface of the display module 1001corresponds to a lower surface 12 of the second base substrate portion112.

According to the display module 1001 shown in FIG. 16, a surfaceroughness of the lower surface 11 of the first base substrate portion111 may be greater than a surface roughness of the lower surface 12 ofthe second base substrate portion 112.

When the weakening of the adhesive force (S20) described with referenceto FIGS. 1 and 7 is performed, a portion of the lower surface 11 of thefirst base substrate portion 111 is carbonized by the ultraviolet rayLZ1. Accordingly, carbides may be generated on the lower surface 11 ofthe first base substrate portion 111, and the carbides may be removed.Due to the generation and removal of the carbides, the surface roughnessof the lower surface 11 of the first base substrate portion 111 may begreater than that of the lower surface 12 of the second base substrateportion 112 onto which the ultraviolet ray LZ1 is not irradiated.

The lower surface 11 of the first base substrate portion 111 may beexposed through the film groove GR1 and the groove GR2. The lowersurface 12 of the second base substrate 112 portion is overlapped withthe adhesive layer 400 and the first film 200, and thus the lowersurface 12 of the second base substrate portion 112 is not exposed.

An inner surface 201 of the first film 200 providing the film groove GR1may be connected to an inner surface 401 of the adhesive layer 400providing the groove GR2. In the embodiment shown in FIG. 16, the innersurface 201 of the first film 200 and the inner surface 401 of theadhesive layer 400 have a straight line shape, but may have a curvedshape according to other embodiments.

An angle (θ) between the lower surface 12 of the second base substrateportion 112 (e.g., a lower surface of the display panel) and each of theinner surface 201 of the first film 200 and the inner surface 401 of theadhesive layer 400 may be an acute angle. This is because the cutting ofthe first film and the adhesive layer (S30) is performed by irradiatingthe laser beam to the upper direction DR3.

The display module 1001 may include a burr BR disposed on the lowersurface of the first film 200 adjacent to the film groove GR1. The burrBR may be formed through the cutting of the first film and the adhesivelayer (S30).

The display module 1002 shown in FIG. 17 may include carbides CB. Thecarbides CB may be disposed on the lower surface 11 of the first basesubstrate portion 111. In further detail, the lower surface 11 of thefirst base substrate portion 111 may have a concave-convex shape, andthe carbides CB may be disposed in a convex portion.

The carbides CB may be generated by the weakening of the adhesive force(S20) described with reference to FIGS. 1 and 7 and may remain in a partof a final product. Accordingly, the carbides CB are not on the lowersurface 12 of the second base substrate portion 112.

According to the display module 1003 shown in FIG. 18, the first basesubstrate portion 111 has a first thickness T1, and the second basesubstrate portion 112 has a second thickness T2 greater than the firstthickness T1.

When the weakening of the adhesive force (S20) described with referenceto FIGS. 1 and 7 is performed, a portion of the first base substrateportion 111 is carbonized by the ultraviolet ray LZ1, or a portion ofthe first base substrate portion 111 is removed in the removing of theportion of the first film and the portion of the adhesive layer (S40).As a result, a structure of the display module 1003 shown in FIG. 18 maybe formed.

According to the display module 1004 shown in FIG. 19, the lower surface11 of the first base substrate portion 111 may be covered by theadhesive layer 400. The adhesive layer 400 may include a first adhesivelayer portion 411 disposed in the first area GRA and a second adhesivelayer portion 421 disposed outside the first area GRA.

The first adhesive layer portion 411 has a third thickness T3, and thesecond adhesive layer portion 421 has a fourth thickness T4 greater thanthe third thickness T3.

In the removing of the portion of the first film and the portion of theadhesive layer (S40) described with reference to FIGS. 1 and 9, theadhesive layer 400 may not be completely removed from the first areaGRA, and thus the first adhesive layer portion 411 may remain.

FIG. 20 is a plan view showing a display module according to anotherexemplary embodiment of the present disclosure; and FIG. 21 is a planview showing the display module of FIG. 20 in a bent state.

Referring to FIG. 20, a display module 1005 may include a display areaDA and a non-display area NA defined therein. The non-display area NAsurrounds the display area DA. The non-display area NA may include firstto fourth areas GRA1 to GRA4.

The display module 1005 may have substantially the same layer structureas one of the display modules 1001 to 1004 described with reference toFIGS. 16 to 19.

The weakening operation (S20), the cutting operation (S30), and theremoving operation (S40) shown in FIG. 1 may be performed on the firstto fourth areas GRA1 to GRA4. Accordingly, the display module 1005 mayhave a shape in which the first film 200 and the adhesive layer 400 areremoved from the first to fourth areas GRA1 to GRA4.

First to fourth cutting lines CL1 to CL4 are provided to the displaymodule 1005. The display module 1005 may be cut along the first tofourth cutting lines CL1 to CL4.

Referring to FIGS. 20 and 21, the display module 1005 may be bent withrespect to a line extending in the first direction DR1 in each of thefirst and second areas GRA1 and GRA2. In addition, the display module1005 may be bent with respect to a line extending in the seconddirection DR2 in each of the third and fourth areas GRA3 and GRA4.

According to the display module 1005 shown in FIGS. 20 and 21, the firstfilm 200 and the adhesive layer 400 are removed from the first to fourthareas GRA1 to GRA4 defined respectively along four sides of the displaymodule 1005, and the display module 1005 is bent along the four sides,but is not limited thereto or thereby. That is, the first film 200 andthe adhesive layer 400 may be removed from two or three sides of thedisplay modules 1005, and the display module 1005 may be bent along twoor three sides.

FIG. 22 is a perspective view showing an organic light emitting displaydevice DP1 according to another exemplary embodiment of the presentdisclosure; FIG. 23 is a plan view showing the organic light emittingdisplay device DP1; FIG. 24 is a cross-sectional view taken along a lineIII-III′ of FIG. 23; and FIG. 25 is a cross-sectional view taken alongthe line III-III′ of FIG. 23 when the organic light emitting displaydevice DP1 is bent.

The organic light emitting display device DP1 shown in FIGS. 22 to 25may have the same structure and function as those of the organic lightemitting display device DP described with reference to FIGS. 12 to 15except for a position of a first area, i.e., a position of a groove.

The organic light emitting display device DP1 may include a displaymodule 1100. The display module 1100 may include a display area DA and anon-display area NA defined therein. The display module 1100 may includea first area GRR defined therein.

The first area GRR may be overlapped with the display area DA. The firstarea GRR may be defined to cross the display area DA. The adhesive layer400 (e.g., a pressure-sensitive adhesive layer) and the first film 200,which are overlapped with the first area GRR, may be removed. That is, agroove GRX overlapped with the first area GRR may be provided in thefirst film 200 and the adhesive layer 400.

The display module 1100 may be bent with respect to a reference axis AX1extending in the first direction DR1. The reference axis AX1 may bedefined under the display module 1100. The display module 1100 may bebent such that two parts of the first film 200, which are divided by thegroove GRX, are closer to each other.

The display module 1100 may be bent in the first area GRR. A bendingarea BA1 may be defined in the display module 1100. The display module1100 may be flat in an area other than the bending area BA1. The bendingarea BA1 may have a width smaller than a width of the first area GRR. Asdescribed above, since the groove GRX overlapped with the bending areaBA1 is provided in the first film 200 and the adhesive layer 400, thedisplay module 1100 may be easily bent in the bending area BA1, and theradius of curvature of the display module 1100 may become small.

Although some exemplary embodiments of the present invention have beendescribed, it is to be understood that the present invention is notlimited to these exemplary embodiments, but various changes andmodifications can be made by one of ordinary skill in the art within thespirit and scope of the present invention as hereinafter claimed.

What is claimed is:
 1. A display device, comprising: a display panelcomprising a first area defined therein and comprising a base substratedefining a lower surface of the display panel, a driving layer on thebase substrate, an organic light emitting diode on the driving layer,and a sealing layer covering the organic light emitting diode; a firstfilm under the base substrate and comprising a film groove definedtherein to overlap with the first area; a second film on the sealinglayer; and an adhesive layer between the base substrate and the firstfilm and comprising an adhesive groove defined therein to overlap withthe first area, wherein a first portion of the base substrate overlapswith the first area, and a second portion of the base substrate isadjacent to the first portion, wherein the first portion of the basesubstrate comprises carbides.
 2. The display device as claimed in claim1, wherein the base substrate comprises polyimide.
 3. The display deviceas claimed in claim 1, wherein the carbides are arranged randomly in thefirst portion of the base substrate.
 4. The display device as claimed inclaim 1, wherein the first portion of the base substrate has a firstthickness, and the second portion of the base substrate has a secondthickness greater than the first thickness.
 5. The display device asclaimed in claim 1, wherein the surface roughness of the first portionof the base substrate is greater than the surface roughness of thesecond portion of the base substrate.
 6. The display device of claim 1,wherein an angle between the second portion of the base substrate andeach of an inner surface of the first film defining the film groove andan inner surface of the adhesive layer defining the adhesive groove isan acute angle.
 7. The display device of claim 1, further comprising aburr on a lower surface of the first film adjacent to the film groove.8. The display device of claim 1, wherein the display panel comprises adisplay area to display an image and a non-display area adjacent to thedisplay area, and the first area is defined in the non-display area. 9.The display device of claim 1, wherein the display panel comprises adisplay area to display an image and a non-display area adjacent to thedisplay area, and the first area is defined to cross the display area.10. The display device of claim 1, wherein the first area crosses thedisplay panel in a first direction when viewed in a plan view and isbent with respect to a reference axis defined in the first area andextending in the first direction.
 11. A display device, comprising: adisplay panel comprising a first area defined therein and comprising alower surface and an upper surface opposite the lower surface; a firstfilm under the lower surface of the display panel and comprising a filmgroove defined therein to overlap with the first area; a second film onthe upper surface of the display panel; and an adhesive layer betweenthe lower surface of the display panel and the first film and comprisingan adhesive groove defined therein to remove a portion of the adhesivelayer overlapping with the first area, wherein a first adhesive layer ofthe adhesive layer overlaps with the first area, and a second adhesivelayer of the adhesive layer is adjacent to the first adhesive layer,wherein the first adhesive layer has a first thickness, and the secondadhesive layer has a second thickness different from the firstthickness.
 12. The display device of claim 11, wherein the secondthickness is greater than the first thickness.
 13. The display device ofclaim 11, wherein the display panel includes a base substrate definingthe lower surface of the display panel, a driving layer on the basesubstrate, an organic light emitting diode on the driving layer, and asealing layer covering the organic light emitting diode; wherein aportion of the base substrate overlapping with the first area comprisescarbides.
 14. The display device of claim 13, wherein the first adhesivelayer contacts the portion of the base substrate overlapping with thefirst area.
 15. The display device of claim 11, wherein an angle betweenthe first adhesive layer and each of an inner surface of the first filmdefining the film groove and an inner surface of the second adhesivelayer defining the adhesive groove is an obtuse angle.
 16. The displaydevice of claim 11, further comprising a burr on a lower surface of thefirst film adjacent to the film groove.
 17. The display device of claim11, wherein the display panel comprises a display area to display animage and a non-display area adjacent to the display area, and the firstarea is defined in the non-display area.
 18. The display device of claim11, wherein the display panel comprises a display area to display animage and a non-display area adjacent to the display area, and the firstarea is defined to cross the display area.
 19. The display device ofclaim 11, wherein the first area crosses the display panel in a firstdirection when viewed in a plan view and is bent with respect to areference axis defined in the first area and extending in the firstdirection.
 20. The display device of claim 11, wherein the first filmcomprises polyethylene terephthalate.